My period is basically an "in the shower only" time, just to make clean-up easier. I love shower play, so it's not a big deal. That said, while I don't mind using dildos on my period, I tend to stick with clitoral vibes until it's over, because I tend to get a bit sore down there during that time.
... Dangit. I just realized I'm due any day now.
Summer + period = not comfy.